A semiconductor device having a semiconductor chip such as an IGBT or MOSFET is used to perform switching for selecting between energization and shutoff at a high speed. During continuous switching operation, the chip produces heat due to power loss as a result of integration of the current flowing through the chip and the voltage applied to the chip. There is a possibility of the chip being broken when the temperature of the chip exceeds an operation guarantee range.
A semiconductor device incorporating an on-chip temperature detection diode to prevent the temperature of the chip from exceeding the operation guarantee range is therefore used (see, for example, Patent Literature 1). Since the VF of the diode lowers in direct proportion to the temperature, the temperature of the chip can be detected by monitoring the value of the VF. For example, a module may be protected from overheat on the basis of the chip temperature detected in the above-described way or the chip temperature may be fed back to an operating condition for a vehicle cooling system, thus enabling optimization of power loss.